The 4 calculators every prediction-market analyst uses. No signup, no paywall, no email required. Bookmark them.
Find the exact stake split between two venues to capture the spread when their prices disagree.
Compute the mathematically optimal stake size given your edge, bankroll, and the market price.
Translate a probability + price into expected value per dollar staked. The bedrock of +EV thinking.
Convert between American odds, decimal odds, fractional odds, and implied probability.
PolySharks AI is grounded on live whale data and can do these calcs for you on demand.
PolySharks.ai is a market-intelligence and analytics platform operated by 8eight8 LLC. The site is provided for informational and educational purposes only — it is not financial, legal, tax, or gambling advice. Past whale performance and historical data carry no guarantee of future outcomes. Trading prediction markets involves substantial risk of loss, including 100% of principal. Users are solely responsible for compliance with the laws of their local jurisdiction — prediction-market access is restricted or prohibited in some US states and countries; verify legality before depositing or trading on Polymarket or Kalshi. PolySharks does not custody funds and is not affiliated with Polymarket Inc. or Kalshi Inc. 18+ only (21+ in some jurisdictions).